NOCTILUCA. 



171 



magnifying power, it appears to be a creature of 

 form nearly round, but with a notch or depression 

 on one part of its circumference. Close by that 

 depression is a little knot of muddy matter, from 

 the centre of which springs a kind of tail, or 

 perhaps proboscis, by the agitation of which the 

 creature rows itself about in the water. The 

 entire form of a Noctiluca is not unlike that of 

 a melon, the proboscis being the stalk. 



